/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

#include "uv.h"
#include "internal.h"

#include <assert.h>
#include <errno.h>
#include <string.h>
#include <sys/un.h>
#include <unistd.h>
#include <stdlib.h>

int uv_pipe_init(uv_loop_t* loop, uv_pipe_t* handle, int ipc)
{
    uv__stream_init(loop, (uv_stream_t*)handle, UV_NAMED_PIPE);
    handle->shutdown_req = NULL;
    handle->connect_req = NULL;
    handle->pipe_fname = NULL;
    handle->ipc = ipc;
    return 0;
}

int uv_pipe_bind(uv_pipe_t* handle, const char* name)
{
    struct sockaddr_un saddr;
    const char* pipe_fname;
    int sockfd;
    int err;

    pipe_fname = NULL;
    sockfd = -1;

    /* Already bound? */
    if (uv__stream_fd(handle) >= 0)
        return -EINVAL;

    /* Make a copy of the file name, it outlives this function's scope. */
    pipe_fname = uv__strdup(name);
    if (pipe_fname == NULL)
        return -ENOMEM;

    /* We've got a copy, don't touch the original any more. */
    name = NULL;

    err = uv__socket(AF_UNIX, SOCK_STREAM, 0);
    if (err < 0)
        goto err_socket;
    sockfd = err;

    memset(&saddr, 0, sizeof saddr);
    strncpy(saddr.sun_path, pipe_fname, sizeof(saddr.sun_path) - 1);
    saddr.sun_path[sizeof(saddr.sun_path) - 1] = '\0';
    saddr.sun_family = AF_UNIX;

    if (bind(sockfd, (struct sockaddr*)&saddr, sizeof saddr)) {
        err = -errno;
        /* Convert ENOENT to EACCES for compatibility with Windows. */
        if (err == -ENOENT)
            err = -EACCES;
        goto err_bind;
    }

    /* Success. */
    handle->pipe_fname = pipe_fname; /* Is a strdup'ed copy. */
    handle->io_watcher.fd = sockfd;
    return 0;

err_bind:
    uv__close(sockfd);

err_socket:
    uv__free((void*)pipe_fname);
    return err;
}

int uv_pipe_listen(uv_pipe_t* handle, int backlog, uv_connection_cb cb)
{
    if (uv__stream_fd(handle) == -1)
        return -EINVAL;

    if (listen(uv__stream_fd(handle), backlog))
        return -errno;

    handle->connection_cb = cb;
    handle->io_watcher.cb = uv__server_io;
    uv__io_start(handle->loop, &handle->io_watcher, POLLIN);
    return 0;
}

void uv__pipe_close(uv_pipe_t* handle)
{
    if (handle->pipe_fname) {
        /*
     * Unlink the file system entity before closing the file descriptor.
     * Doing it the other way around introduces a race where our process
     * unlinks a socket with the same name that's just been created by
     * another thread or process.
     */
        unlink(handle->pipe_fname);
        uv__free((void*)handle->pipe_fname);
        handle->pipe_fname = NULL;
    }

    uv__stream_close((uv_stream_t*)handle);
}

int uv_pipe_open(uv_pipe_t* handle, uv_file fd)
{
    int err;

    err = uv__nonblock(fd, 1);
    if (err)
        return err;

#if defined(__APPLE__)
    err = uv__stream_try_select((uv_stream_t*)handle, &fd);
    if (err)
        return err;
#endif /* defined(__APPLE__) */

    return uv__stream_open((uv_stream_t*)handle,
        fd,
        UV_STREAM_READABLE | UV_STREAM_WRITABLE);
}

void uv_pipe_connect(uv_connect_t* req,
    uv_pipe_t* handle,
    const char* name,
    uv_connect_cb cb)
{
    struct sockaddr_un saddr;
    int new_sock;
    int err;
    int r;

    new_sock = (uv__stream_fd(handle) == -1);

    if (new_sock) {
        err = uv__socket(AF_UNIX, SOCK_STREAM, 0);
        if (err < 0)
            goto out;
        handle->io_watcher.fd = err;
    }

    memset(&saddr, 0, sizeof saddr);
    strncpy(saddr.sun_path, name, sizeof(saddr.sun_path) - 1);
    saddr.sun_path[sizeof(saddr.sun_path) - 1] = '\0';
    saddr.sun_family = AF_UNIX;

    do {
        r = connect(uv__stream_fd(handle),
            (struct sockaddr*)&saddr, sizeof saddr);
    } while (r == -1 && errno == EINTR);

    if (r == -1 && errno != EINPROGRESS) {
        err = -errno;
        goto out;
    }

    err = 0;
    if (new_sock) {
        err = uv__stream_open((uv_stream_t*)handle,
            uv__stream_fd(handle),
            UV_STREAM_READABLE | UV_STREAM_WRITABLE);
    }

    if (err == 0)
        uv__io_start(handle->loop, &handle->io_watcher, POLLIN | POLLOUT);

out:
    handle->delayed_error = err;
    handle->connect_req = req;

    uv__req_init(handle->loop, req, UV_CONNECT);
    req->handle = (uv_stream_t*)handle;
    req->cb = cb;
    QUEUE_INIT(&req->queue);

    /* Force callback to run on next tick in case of error. */
    if (err)
        uv__io_feed(handle->loop, &handle->io_watcher);
}

typedef int (*uv__peersockfunc)(int, struct sockaddr*, socklen_t*);

static int uv__pipe_getsockpeername(const uv_pipe_t* handle,
    uv__peersockfunc func,
    char* buffer,
    size_t* size)
{
    struct sockaddr_un sa;
    socklen_t addrlen;
    int err;

    addrlen = sizeof(sa);
    memset(&sa, 0, addrlen);
    err = func(uv__stream_fd(handle), (struct sockaddr*)&sa, &addrlen);
    if (err < 0) {
        *size = 0;
        return -errno;
    }

#if defined(__linux__)
    if (sa.sun_path[0] == 0)
        /* Linux abstract namespace */
        addrlen -= offsetof(struct sockaddr_un, sun_path);
    else
#endif
        addrlen = strlen(sa.sun_path);

    if (addrlen >= *size) {
        *size = addrlen + 1;
        return UV_ENOBUFS;
    }

    memcpy(buffer, sa.sun_path, addrlen);
    *size = addrlen;

    /* only null-terminate if it's not an abstract socket */
    if (buffer[0] != '\0')
        buffer[addrlen] = '\0';

    return 0;
}

int uv_pipe_getsockname(const uv_pipe_t* handle, char* buffer, size_t* size)
{
    return uv__pipe_getsockpeername(handle, getsockname, buffer, size);
}

int uv_pipe_getpeername(const uv_pipe_t* handle, char* buffer, size_t* size)
{
    return uv__pipe_getsockpeername(handle, getpeername, buffer, size);
}

void uv_pipe_pending_instances(uv_pipe_t* handle, int count)
{
}

int uv_pipe_pending_count(uv_pipe_t* handle)
{
    uv__stream_queued_fds_t* queued_fds;

    if (!handle->ipc)
        return 0;

    if (handle->accepted_fd == -1)
        return 0;

    if (handle->queued_fds == NULL)
        return 1;

    queued_fds = handle->queued_fds;
    return queued_fds->offset + 1;
}

uv_handle_type uv_pipe_pending_type(uv_pipe_t* handle)
{
    if (!handle->ipc)
        return UV_UNKNOWN_HANDLE;

    if (handle->accepted_fd == -1)
        return UV_UNKNOWN_HANDLE;
    else
        return uv__handle_type(handle->accepted_fd);
}
